1. Field of the Invention
The present invention pertains to apparatus for use with internal combustion engines for reducing the noise thereof and for reducing the noxious components of the exhaust gases emitted therefrom. More specifically, the present invention pertains to apparatus particularly suitable for use with natural gas fueled engines to silence the exhaust thereof and to reduce the nitrogen oxides, carbon monoxides and unburned hydrocarbons from the exhaust of such engines.
2. Brief Description of the Prior Art
Silencers or mufflers for internal combustion engines have existed for many years. Most industrial silencers utilize some type of shell or housing in which is mounted various types of baffles for reducing the noise produced at the exhaust of an internal combustion engine.
In recent years, attention has also been directed to reducing the noxious gases emitted in the exhaust of an internal combustion engine, e.g. nitrogen oxide, carbon monoxide and other unburned hydrocarbons. As interest and concern in pollution of the atmosphere continue, particularly as reflected in state and federal air regulations, the search continues for effective means for reducing these noxious emissions. Equipment for reducing noxious emissions from internal combustion engines usually provide some type of catalyst which converts the gases to water, nitrogen, carbon dioxide and other harmless emissions.
Most exhaust emission control apparatus, particularly those for silencing and reducing the noxious emissions of internal combustion engines in industrial applications utilize separate devices for noise reduction and noxious gas reduction. This probably results from the fact that silencers or mufflers are commonly made by one company and catalytic converters by another company. Since these devices are made separately but must be connected in series to an engine exhaust, the pressure drop therethrough is relatively great, resulting in decreased fuel efficiency. In addition to increased operating expense, two separate units result in greater installation cost.